Smokeless fuel economizing furnace



July 7, 1931. J. B. EHRLICH SMOKELESS FUEL ECONMIZING FURN-ACE Filed Jan. 30. 1928 2 Sheets-Sham Q4 TTU//vef July 7, 193.1.

J. B. EHRLICH sMoKELEss FUEL EcoNoMIzING FURNACE 2 Sheets-Sham 'Filed Jan? so, 192e n Patented Jury 7, 192.1

PATENT OFFICE JOHN B. EHRLICH, 0F PORTLAND, OREGON SMOKELESS FUEL ECONOMIZING FURNACE Application led January 30, 1928. Serial No. 250,518.

This invention relates generally to stokers for burning cut fuel, and particularly to a special form of Stoker adaptable to household or industrial purposes.

rihe first object' `of this invention is to secure ,complete combustion.

rlhe second object is to adapt the device to all kinds of solid fuel in cut or crushed form.

The third object is to secure increased efficiency over other forms of stokers of the same type.

The fourth object is to so construct the deviceI that it can be easily cleaned.

rlhe fifth object is to secure better circulation of air, thereby more completely extracting the heat which has been conducted to the metal parts of the furnace.

The sixth object is to so construct the furnace as to secure quick heating.

The seventh object is to secure a uniform distribution of air from all of the ducts leading from thefurnace.

The eighth object is to make it possible to operate the grates at the furnace or from a remote control, either manually or by power.

The ninth object is to cause all of the air passing through the furnace to come in close contact with the heated metal parts thereof. The tenthobject is to'provide a special form of tiltable rotatable grate.

The eleventh object is to provide a special form of self-cooling and self-'cleaning grate.

The twelfth object is to heat the air supplied above and below the grates.

The thirteenth object is to provide an agitator in the fuel feed hopper to prevent the clogging of the fuel.

The fourteenth object is to provide an outlet in the fuel duct for the escape into the combustion chamber of ases either generated in the fuel supply uct or which may back into same from the combustion chamber.

These, and other objects, will become more apparent from the specification following as illustrated in the accompanying drawings, of which:

Figure 1 is a longitudinal section through the furnace. Figure 2 .is a. fragmentary horizontal section taken along the line 2-2 in Figure 1. Figure 3 is a fragmentary section.

Figure 4 is a transverse section taken along the line 4-4 in Figure 1. Figure 5 is a horizontal section taken along the line 5-5 in Figure 4. Figure 6 is a fragmentary horizontal section taken along the line 6-6 in Figure 4. 55

.Similar numbers of reference refer to similar parts throughout the several views.

Referring in detail to the drawings, the furnace includes a base 12 upon which is mounted an ash pit casing 13 upon which is 60 mounted a lire box lining 14 whose outwardly extending flange l5 is provided with openings l-A and rests upon the base 12. On the flange 15 rests a lire box casing 16 which is spaced from the lining 14 and forms an 65 air heating chamber 17. The lining 14 is provided with perforations 18 from which air passes from the chamber 17 into the combustion area. A plate 19 is pivotally mounted 'on the trunnions 2O which journal in the lin- 0 ings 14. The upper edges 21 of the linings 14 are inturned and provided with perforations 22 which provide a down draft into the combustion area and assist in agitating the burning gases. The edges 21 are also provided 75 with an out-turned ortion 23 which bear against the upper fire ox casing 24. Within the upper lire box casing 24 is mounted an air preheating manifold 25 whose downturned ends 26 pass through the sloping sides 23 of the lire box lining'14. The manifold 25 is provided with a check damper 27 adapted to be controlled by a chain 28from a remote point. Above the manifold 25 is placed a fire box dome 29 whose upturned portion 30 has mounted on the top thereof a smoke distributing manifold 31 having six downwardly extending branches 32, 33 and 34 whose lower ends are joined by the horizontal ducts 35, whose rearward end is closed and whose forward end is provided with a door 36 for` cleanout purposes.

' The manifold 31 is provided with a partition 37 between its ducts 33 and 34, and the upper ends of the ducts 34 are joined by a downturned duct 38 to a smoke outlet ue 39 whose forward end 40 slips 'over the flanged opening 41 at the rear of the upper lire box casing' 16. The lianged opening 41 is pro- 1.00 vided with a damper 42 by means of which a I direct draft to the stack may be secured. The` vof the adjacent bars. Each bar 47 is rotatably mounted by means of vtrunnions 50 and provided with a sprocket wheel 51. A chain 52 passes around all of the sprockets and will rotate all of the bars 47 in the same direction. The shaft 50-A is extended to permit same to be driven by a second chain 53 from the motor 54. Obviouslythe chain 53 may be operated manually as well as with a motor, and the control may be near at hand or remote as seems most desirable. l

The angle of thefraine 46 can be controlled by the bolt 55 which passes through the frame extension 56 and the slot 57 in the arm 58. Slots 59 are provided in the supporting member 60 to permit the vertical movement of the grate bars.

Fuel 61 is admitted to the grates through a magazine 62 hinged at its upper end by means of a pin 63 to the furnace front 64, and also at its lower end by means of a pin 65 to the furnace front 64. A fuel control door 66 is mounted on the hinge 67 and its position is controlled by the lever 68 and the notched rod 69 which engages a lug 70. On the under side 71 of the magazine 62 is hinged a plate 72 on the pin 73, and the lower-end of the plate 72 bears against the foremost bar 47 whose rotation provides'a slight agitating movement for the plate 72 and prevents the choking of fuel in the magazine 62.v

Outlet openings 74 in the end 75 of the fuel magazine 62 permit any accumulation of gases to escape into the combustion area and be burned instead of backing upwardly through the fuel and escaping into the furnace room. A cover 76 is provided for the magazine 62. A chain 77 which passes around the suspended pulley 78 is utilized to supportthe upper end'of the magazine 62, which may be swung on either of the pivots 63 `or 65 depending upon the reason for such swinging. That is to say, it will be swung `on the lower pivot when filling the magazine i 62 with fuel, or on the upper pivot when it is desired to gain access to the grates.

The operation of this form of the furnace is as follows: Fire is started on the grate bars 47 and fuel is gradually allowed to pass from the magazine 62 onto the grate bars 47 under the control of the rod 69, during which time the damper 42 is held-open to provide a direct draft to the stack. As soon as the fire is well under way and the furnace parts warmed up the draft'42 is closed, which causes the burned gases to pass upwardly]7 around the preheating manifold 25, throug the manifold 31, then downwardly through the branches 32 and 33, then rearwardly along the ducts 35, then upwardlythrough the branches 34 and then downwardly through the downturned duct 38 into the smoke stack, during whichtime the burned gases have surrendered practically all of the heat developed in the combustion. Part of this heat has been taken up bythe manifold 25 and its downturned ends 26 and is used to preheat the air which passes through the perforations 18 and 22 into the combustion arca, and also through the openings 15-A- to the under side of the grate bars 47.

It can be seen that by this arrangement an ideal condition isv secured, namel that the air delivered to the combustion is preheated, not at the expense of heat which should ordinarily be ldelivered to the home, but which has been salvaged from the burned gases ordinarily passing out of the smoke stack. Not only does this secure an economy in fuel consumption but it completely eliminat-cs all smoke and soot ordinarily produced by the incomplete burning of fuel.

I am aware that many forms offurnaces have been constructed in the past; I therefore do not claim such devices broadly, but I do intend to cover all such forms and modifications thereof as fall fairly within the appendedclaims.

1. A furnace having in combination an in clined grate surface comprising a' pair of side frames, a plurality of hollow hexagonal grate bars rotatably mounted in said frames extending therebetween and having openings forme-d in the sides thereof, and having encircling flanges along the length of each bar,

the Hanges on each bar lying intermediate to the flanges on adjacent bars, means for varying the degree of inclination of said grate surface, and an agitator having one end resting on a hexagonal grate bar.

2. In a furnace, the combination of a tiltable inclined grate consisting of a pluralityof hollow grate bars of polygonal cross section `having their outer surfaces provided with openings communicating with the interior thereof, a fuel magazine ada ted to deliver fuel to the uppermost grate ar, an agitating plate within said magazine having its lower end resting upon the irregular surface of the uppermost bar and adapted to be operated thereby for'the purpose of agitating fuel within the magazine, and means for agitating all of said gratebars in the same direction in a manner to feed the fuel downwardly along said inclined grate.

3. In a furnace, the combination of -a pair of til'table spaced sidel frames, a plurality of tubular grate bars rotatably mounted in and extending, between said Aside frames having openings in theA outer surface thereof communioating with the interior of the bars, the grate thus formed lying. normally in an inclined plane, a fuel hopper adapted to discharge fuel upon the uppermost end of said grate, an agitator plate hinged within 'said o hopper having its lower end resting upon the uppermost grate bar, a door for controlling the rate'of iow of fuel from said hopper to said grate, and a plate hinged above the lower end of said grate having its lower end 5 swung close to said grate surface.

4. The subject matter of claim 3, and means for supplying air in regulated quantities above and below said grate surface.

JOHN B. EHRLICH. 

